Distinguished by the following characters: head plump, more or less rounded, dorsoventrally compressed; mouth slightly oblique, forming an angle of about 20° to 25° with body axis; maxilla extending under middle to rear margin of eye, occasionally only to front of pupil; profile of snout steeply rounded in lateral view; interorbital narrow equal to or less than one-half eye length; gill-rakers on outer face of first arch short and slender; those on second and following arches shorter; mandibular frenum without lobes; anterior nostril a short tube, posterior nostril with a raised rim; most males with first, rarely second, first dorsal-fin spines filamentous, the first reaching to last first dorsal-fin spine base to second ray base of second dorsal fin, and occasionally to the ninth dorsal-fin ray base; scales absent (Ref. 87125).